Susceptible
by Bleu Jai
Summary: Just a quick one shot of Sonic and Shadow. Loosely based on a headcanon among friends I have where Shadow doesn't know what basic human ailments are. Basic illnesses or w/e make him panic and increasingly afraid and yadda yadda. So what happens when Sonic wants to boast about the speed of his plane? **do NOT read if you have a acrophobia or emetophobia**


Shadow didn't understand what was wrong with him. Usually he'd be fine in any sort of situation, seeing as he was artificial and immune to any illness, but something about being in Sonic's plane with him made him feel… off. And it wasn't just because he was his long time rival.

Shadow noticed that his hands were rather shaky and sweaty, he kept getting dizzy spells, and it felt as if his throat was too tight which made swallowing difficult. Strangest of all for him, was his stomach felt really displeased. It felt like it was trying to force its way up to his throat, as if it were trying to escape the current oblivious torture his rival was giving him.

Adding in the feeling that his seat belt felt too constricting around his midsection and that every time the plane moved at all, it sent an intense spike of icy nausea through his veins. It kind of scared him; he's never experienced something so uncomfortable before. Especially not in his own body.

"Alright Shads, you ready to see what Tails got done modifying?" Sonic called out over the sound of the propeller.

The black and red hedgehog hesitated to speak as he swallowed back another thick amount of saliva that flooded his mouth. Not from fear, no no, but from intense nausea. He was certain it was from the blue blur's carelessness when it came to flying: whizzing high through the clouds and making sharp movements in the sky with the occasional steep nosedive a few feet down before quickly ascending once more.

"Does it make you eject from the cockpit and send you tumbling to the ground?" He tried to sound as normal as possible, forcing himself to ignore the sickening churning in his stomach as he spoke.

Predicting such a cold reply, Sonic gave a cocky laugh before turning to face him. Once again proving to Shadow that he had very little concern for safety.

"Nah, not even close! It's the Booster near the tail of the plane!" The slightly younger hedgehog pointed out.

Shadow gave him an unamused glare, trying to act just as, if not more, cool and collected as him. Harder to do when you felt like losing your lunch at any second.

"The what?"

"The Booster!" Sonic casually repeated as he turned his attention back to the Tornado's controls. "Recently when we went on a little cruise around cloud village here," he gestured to the plethora of clouds besides them, "I blew out the previous Booster. Right now, the Tornado isn't actually going that fast, just a mere 450 kilometers an hour, which is way too slow for me! So I had asked Tails if he could install another one, this time more suited to my specifications!" Sonic turned to face Shadow, giving him his full attention rather than paying attention to the plane. "I thought I'd test it out with the only other person that I know has a love for speed like me– you!"

"Thoughtful idea, but stupid." Shadow spoke coldly, crossing his arms.

He wasn't one for showing any sign of weakness, even when he was badly injured, yet with what he was feeling right now, it was becoming more and more difficult to hide his mounting discomfort. Especially with Sonic staring him down with that stupid eager grin.

"Aw c'mon Shads!" The blue blur reclined in his pilot seat, "I wanna show ya just how fast this baby can go! With as much speed as she carries–"  
"How much damn speed do you _need_?"  
"Just enough to feel satisfied– anyway, Tails predicts that the Tornado's booster can break the sound barrier!" Sonic gave a prideful, and rather conceited, laugh before he glanced at his rival in the backseat. "Now buckle up, faker! ENGAGING THE SONIC BOOST!"

With a delightful shout to the sky, the cobalt hedgehog slammed his thumb onto the "BOOSTER" button on the control panel. Instantly, the biplane went from 400km to over 1000km.

The drastic kinetic change in speed sent shock-waves of adrenaline through Sonic. He laughed and threw his hands up as they pierced the clouds, taking hold of the yoke and drifting quickly between altitudes. He sharply turned to do a swift corkscrew followed by a steep nosedive near the ocean. He cheered with each adrenaline rush as he pulled down on the controllers, sending the plane into a quick ascension.

Now, Shadow could honestly care less about Sonic, being his polar opposite and all, but going _this _fast was extremely dangerous. Not that he minded the excitement and adrenaline rush he got as well, but Sonic being, well, _Sonic_, this was a recipe for a disaster. One wrong movement literally meant life or death. Bone chilling, to say the least.

In addition to the slight fear for his own safety at the hands of his thrill-seeking rival, Sonic's swift piloting and showing off tricks did nothing for the intensity of sickness rising in his body. With every corkscrew, upside down movement, and nosedive after nosedive, Shadow was having a harder and harder time trying to keep his composure. Fear over what he was experiencing was completely occupying his mind, accompanied by the uncomfortable gurgling in his stomach.

His ears turned back involuntarily as he held onto the back of Sonic's pilot seat for support as he slightly leaned over and lowered his head to try and hide his obviously pale complexion. He silently let out a strained sigh through grit fangs as he felt his stomach twist in pure nausea.

He couldn't lie to himself anymore– he was starting to panic. Never before has he felt such an overwhelming feeling of discomfort, at the hands of motion no less. Something he's been familiar with his whole life, especially having flown before and never experiencing symptoms like this. The more he thought, the more he racked his brain for some sort of conclusion. He silently groaned as his stomach gave an unpleasant rumble from another sharp turn.

Shadow's eyes shot open as his stomach violently lurched at another nosedive, saliva flooding his mouth as he swiftly slapped his hand over his mouth. He stared down in panicked anxiety, trying to keep his stomach under control. What he wouldn't give to Chaos Control put of this situation right now. This has to be the epitome of suffering: your body acting out against your will. His eyes tightly shut once more as he retched into his palm, thanking the gods that the plane's propeller was loud enough to silence him. Was he going to survive this was there something fatally wrong with him? Maybe he was–

"Wooo!" Sonic chuckled as the swift sonic boom began to slow carefully, the booster having been exhausted as he piloted through the sky once more. Once back to the plane's default speed, Sonic flicked on the autopilot and turned to see the look on his rival's face. "How was that, Shadow? Wasn't that rad?!"

It took Sonic a minute to notice that Shadow wasn't sitting up like he was before, rather leaning over with his body shaking.

"Uh… Shads?" The cobalt hedgehog raised a curious brow. "You alright?"

Shadow's blood ran cold at Sonic's question, forcing himself to act as if he were fine. He sat up, doing his hardest to not retch from the movement alone, and nonchalantly crossed his arms.

"O-of course I'm alright, hedgehog." His voice was shaky, mentally kicking his ass for not maintaining his calm tone.

Luckily, Sonic wasn't as oblivious as Shadow had hoped.

"Are you sure? You look really pale." He tilted his head, resting his chin in his palm as he watched Shadow's trembling state.

"Can we just land now, for Chaos sake? I've had enough of this stupid–" Shadow stopped himself as he felt his throat tighten and a hot acidic taste rose up. He managed to keep himself composed in his careless position.

Marking it up to his rival's irritability, Sonic groaned in annoyance and turned back around. "Alright alright, enough showing off. Let's land this baby." He announced as he began to steer the plane down in a much more gentler way than before.

With Sonic no longer paying attention to him, Shadow covered his mouth once more. His voice now completely lost as the sour taste of stomach bile flooded his mouth. He lowered his head again, trying his hardest to control his panic and keep himself from vomiting. His cheeks swelled as he tightened his hand against his mouth, trying to contain it. His other hand clenched into a fist as he urgently screamed in his head that he needed to get out ASAP.

With a hard screech and the propeller slowing as they landed, the tornado came to a slow half-stop before Shadow jumped out of his seat. He couldn't wait for it to make a full stop, he had to leave now. He stumbled towards a tree and disjointedly clung to it as he bent over, sour and hot stomach acid spilling from his mouth onto the grass below. He coughed harshly before gagging up more bile as his stomach continued to clench in sickness.

"Ohhh I see."

Shadow's ears instinctively turned to Sonic's voice before he groaned in annoyance.

"So that was too much speed for ya, eh faker?" Sonic boasted as he stood behind the older teen, arms crossed with a smug expression.

Shadow tried to respond, but couldn't so much as get a syllable out before his stomach lurched again, forcing the half-breed to pitch forward once more. He coughed as the burning in his chest intensified with each sickening churn of his stomach, still clearly trembling as he supported himself with his hands on his knees.

"Man, I never knew the "ultimate life form" got motion sick. You'd think that you would be immune to something so human." Sonic spoke as he set a comforting hand to Shadow's back, stroking his back quills down in an attempt to smooth them out.

Motion sick. Yes, that's what that was called. He vaguely remembered his creator mentioning something about that, that it was commonplace for humans to experience under certain circumstances.

Part of his initial panic was now at ease, feeling relieved he knew what was wrong with him. He never had this problem before, though. Maybe it was because Sonic was so careless and _fast_… but they both knew that he, Shadow, was most certainly faster than that damned blue rat.

"Got it all out, buddy?" Sonic asked, stifling a laugh as he kept his palm on Shadow's back.

Panting heavily, Shadow hesitated on speaking just in case. His stomach was far from settled, but the nausea was significantly lessened. He coughed sparsely before straightening himself up, leaning against the tree for support. As he opened his crimson eyes, he saw Sonic smirking and stifling laughs… which pissed him off to no end.

Angered, he grabbed Sonic by his peach torso and glared daggers into him.

"Speak of this to _anyone_ and you're dead meat, you blue rat."


End file.
